GPD Optoelectronics manufactures a broad range of Ge and InGaAs photodetectors to meet the most demanding military and commercial applications. This brochure contains technical specifications for Ge, dual (Si/Ge) detectors, and TE cooled Ge photodiodes.
DARK CURRENT (ID)
Custom devices and packages are also available.
Responsivity vs. Wavelength Comparison 1
(A/W) Responsivity
SHUNT RESISTANCE (RSH) The resistance of a photodetector at or near zero bias; shunt resistance values in this catalog are calculated at 10mV reverse bias. MAXIMUM REVERSE VOLTAGE (VRM) The maximum reverse voltage that may be applied without damaging the detector.
Germanium
Silicon
The current through a photodetector when a specified reverse bias is applied under conditions of no incident radiation.
RESPONSIVITY (R) The photocurrent output per unit incident radiant power, usually at a specified wavelength.
0.1 InGaAs
NOISE EQUIVALENT POWER (NEP) 0.01 400
600
800
1000
Wavelength
1200
1400
1600
1800
(nanometers)
The incident radiant power that creates a signal to-noise ratio of one at the photodetector output. JUNCTION CAPACITANCE (CJ)
Both Germanium and InGaAs are sensitive to light in the near-infrared region of the spec trum. While InGaAs detectors offer better noise performance, Ge detectors offer better linearity and cost advantages, particularly where a large detection area is required.
The total device capacitance, usually measured at a specified reverse bias and frequency. CUTOFF FREQUENCY (fc) The frequency at which the responsivity de creases by 3 dB from the DC responsivity value. It can be calculated from the load resistance and the junction capacitance. fc = 1/(2πRLCJ)
Table of Contents Glossary of Terms Operating Circuits Ge pn Detectors Two-color Detector Package Outline Drawings
Designed for zero reverse bias applications requiring high shunt resistance. Designed for zero reverse bias applications. Designed for < 5V reverse bias applications. Designed for high speed applications with reverse bias > 10V. Mounted on a one- or two-stage thermoelectric cooler for low-noise applications.
Special Options • High response at short wavelength available • BNC connectors • Thermoelectric coolers (1- and 2-stage) • Neutral density filters • Bandpass Filters • AR-coated lenses/windows • Custom devices including arrays • Calibrated spectral response